u-boot/arch/mips/cpu/cm_init.S
Paul Burton b2b135d980 MIPS: Map CM Global Control Registers
Map the Global Control Registers (GCRs) provided by the MIPS Coherence
Manager (CM) in preparation for using some of them in later patches.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
2016-09-21 15:04:04 +02:00

45 lines
946 B
ArmAsm

/*
* MIPS Coherence Manager (CM) Initialisation
*
* Copyright (c) 2016 Imagination Technologies Ltd.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <asm/addrspace.h>
#include <asm/asm.h>
#include <asm/cm.h>
#include <asm/mipsregs.h>
#include <asm/regdef.h>
LEAF(mips_cm_map)
/* Config3 must exist for a CM to be present */
mfc0 t0, CP0_CONFIG, 1
bgez t0, 2f
mfc0 t0, CP0_CONFIG, 2
bgez t0, 2f
/* Check Config3.CMGCR to determine CM presence */
mfc0 t0, CP0_CONFIG, 3
and t0, t0, MIPS_CONF3_CMGCR
beqz t0, 2f
/* Find the current physical GCR base address */
1: MFC0 t0, CP0_CMGCRBASE
PTR_SLL t0, t0, 4
/* If the GCRs are where we want, we're done */
PTR_LI t1, CONFIG_MIPS_CM_BASE
beq t0, t1, 2f
/* Move the GCRs to our configured base address */
PTR_LI t2, CKSEG1
PTR_ADDU t0, t0, t2
sw zero, GCR_BASE_UPPER(t0)
sw t1, GCR_BASE(t0)
/* Re-check the GCR base */
b 1b
2: jr ra
END(mips_cm_map)